Research Ideas - George Gadanidis
Disseminating math education research through performance, and studying the process and impact of research performance. Funded by the Fields Institute, Random Acts of Math brings math ideas to young children and their parents. Music videos of the Math
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The Right-Angle Triangle Solver - Steve Ayers
Input two sides of a right triangle, or one of its sides and one of its angles, and this site calculates the remaining sidelengths and angles. Also, convert decimals and fractions, and imperial and metric units of measure. Requires JavaScript.
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Rite Item - Jim Preston
Software to download: ANYANGLE (Windows, DOS; a geometry solver that provides a method of finding answers to problems involving triangles, and offers scale views and supplementary data to back up the numerical results); and PARTYDOT (a program for creating
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Rockin' the Standards
Musical recordings by a rock band led by a veteran elementary school teacher who takes the lyrics from common tunes and changes them to help kids remember what they've been taught in school. Each of the fourteen songs on the album "Rockin' the Standards
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Science Museum Math Exhibit - The Geometry Center
A museum exhibit on triangle tilings that contains sophisticated concepts such as tilings of the sphere and the relation between tilings and the Platonic and Archimedean solids: the sum of the angles of a planar triangle is always 180 degrees. Repeated
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Science Museum of Minnesota
Natural history and technology. See the world's largest Camptosaurus dinosaur skeleton, touch a tornado, play the congas, do some serious Internet surfing, or test the waters of the Mississippi River. The museum is Minnesota's most popular indoor cultural
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Shelley Walsh
Syllabi and notes for math courses from arithmetic review to beginning calculus. Download MathHelp a tutorial program with problem sets for Mac or PC, or learn how to use MathHelp to create your own tutorials. Brief Mathematics Articles present concepts
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The Shikaku Room - Paul Hutchinson
Given a few numbered squares in a larger grid, block out rectangular and square sections so that each component piece contains the one number that represents its area. Randomly generate or create your own grids — from 4 × 4 up to 20 ×
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Software - Bill White
These Flash apps provide online practice deriving some unknown property of a figure given its other measures. Find the area of a trapezoid given its two base lengths and height; find one of its bases given its area and height; find its height given its
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Some Variations on the Theme of Polyominos - Recmath
Patterns that illustrate how the squares of polyominos are connected to each other. Examples of polyominos with a grid superimposed to illustrate the individual squares; with a line that joins the mid-point of two adjacent square if the squares are connected.
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Spidron System - Daniel Erdely
Erdely calls a planar, plane-filling object a Spidron. Upon three-dimensional deformation subject to specific constraints, the planar system generates a regular, dynamic, geometrical construction. Erdely's experiments have led to the idea of creating
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Square of the Hypotenuse - Ivars Peterson (MathTrek)
Some history of the legend of the discovery of the Pythagorean theorem: in his textbook The History of Mathematics, Roger Cooke of the University of Vermont describes how the Babylonians might have discovered the Pythagorean theorem more than 1,000 years
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Stickets - Wanderlands
A puzzle game for iPhone "that forgot Tetris existed": drag tri-colored L-shaped blocks onto a grid and tap contiguous, similarly colored areas comprised of three or more squares in an ongoing quest to preserve space on the grid. The app also challenges
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Tangram Page - S. T. Han
All about tangrams, an ancient Oriental toy that has 7 pieces: 5 triangles in different sizes, 1 square, and 1 parallelogram. The object of the game is to form a given shape using all 7 pieces. Introduction, Puzzle of the Month, PC/Mac Software, Articles
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Tangrams - J. L. Read; Enchanted Mind
A tangram applet that allows you to rearrange the seven forms to exactly reproduce the given image. To move the pieces, drag them with the mouse. To rotate pieces, click with the right mouse button or (on the Mac with a one-button mouse) click while holding
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Tangrams - Tom Scavo
Tangrams, a puzzle that helps develop spatial-visualization skills, may also be used to introduce or reinforce geometric concepts such as congruence, similarity, symmetry, etc. This unit for grades 4 through 6 uses tangrams to compute the area of polygons
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Teaching Ideas for Primary Teachers: Maths
Math activities for ages 5-11 include a puzzle display, shapes worksheets, ideas for making a maths dictionary, a questioning technique, and many more games, worksheets, and activities for the classroom.
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Tessellated Polyhedra - Jill Britton
Full-page printable nets of each of the regular polyhedra, decorated with individual surface tessellations in full color. A higher-resolution black-and-white version of each tessellated net appears in Polyhedra Pastimes, by Jill Britton, published by
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TheXorb - Jagan Deb
Online calculators for the slope and y-intercept of linear equations; standard deviations; mean, mode, and range; the Pythagorean Theorem; and properties of geometric figures such as triangles, squares, circles (circumference given area; area given diameter;
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A Thing In Common - Cut the Knot!, Alexander Bogomolny
Two applets, both of which use the Pythagorean theorem: a puzzle (Draw an {N/D} star polygon - a polygon whose N vertices are uniformly distributed on a circle, but each vertex is connected to its D-th neighbor. Regular polygons correspond to D = 1, and
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